THE liUII.DINC; OF AN ISLAND. 1 3 



In a tropical island like ours many forms of it are familiar to a visitor to 

 the beaches ; but a cursory examination of the dead specimens will not enable 

 us to understand their nature. In school books \vc sometimes fmd the praises 

 of the "coral insect" sung as the industrious builder of islands; but, as a mat- 

 ter of fact, there is no coral insect, neither does the living coral "build" in 

 any proper sense of the word. To understand what a coral is we must first 

 study the -animal llowers " tliat we find along our shores. It is true that 

 some of the most beautiful oi these, namely those which spread out their 

 "petals" from the tops of tubes and are quick in withdrawing them, are 

 worms,'"" and have no familv connection with the corals ; but the fleshy ones 

 with stickv arms around their outer edge (sea-anemones) are first-cousins to 

 the corals. Most of these animal-flowers live separately ; but on the reefs, 

 and occasionally along the shores, too, a form of these curious creatures may 

 be found which live in extensive colonies, the bodies all joined together by a 

 sheet of flesh below, the upper parts showing as pretty stars with green cen- 

 tres, closely packed together, forming a beautiful piece of natural carpeting. 

 This form carries us very near to the corals ; for if we now think of the stars 

 as still further reduced in size, and think of them and the fleshy sheet which 

 unites them as depositing a limestone foundation, we come very near to a 

 clear conception of what a coral is. When we see the stars on the stony coral 

 we now know that they were deposited below the stars on the living animal. 



A live coral, then, is a compound animal, feeding its hundreds, or may be 

 thousands, of little stomachs on whatever suitable food the waves may bring 

 to them, and feeding them with the help of the star-like sets of tiny arms that 

 wave over the gelatinous surface, while, as the whole grows, carbonate of lime 

 is deposited below and in the partitions which go from the outer wall of each 

 ceH towards its centre. Thus, the living coral does not din'/d the stony base, 

 or the stars, any more than a child builds the bones in its body. In both cases, 

 that of the child and the coral alike, the stony material is extracted from the 

 food and lodged in its proper place by the vital processes. 



The creatures mentioned above constitute the family of the true corals. 

 There are, however, closely allied kinds which form hoimy skeletons, such as 

 the well known yellow sea-fans and purple sea-fans, and the branching sea-rods, 



* Some of the sea-worms of the West Indian shores are among the most beautiful objects in creation. 

 The large Sabella, for example, that inhabits the Lagoon at Christiansted and may occasionally be seen 

 along the shores of the harbour, suggests, with its corolla-like fringe of breathing organs coloured in con 

 centric bands of brown and white, a large and beautiful chrysanthemum. There are other beautiful but 

 smaller kinds, for instance, a bright yellow one always in motion, swinging its arms to right and left in 

 regular time ; another, a brown one, that peeps through the sand in groups, and is so sensitive to light and 

 shade that merely passing the hand over the water above it causes the instantaneous withdrawal of the 

 "flower" into the tube. None of these, however, contributes anything to the materials accumulating at 

 the sea bottom, their tubes being simply leathery. On the other hand, there are some kinds which have 

 hard, shelly tubes, and fragments of these may often be found in the sea-sand. There is, for instance, the 

 curious brown Serpula. which coils itself in masses over the rocks, and sometimes becomes an actual pro- 

 tection for them. There are others again which form very small shells, flat white coils that may be fre- 

 quently found adhering to stones and other objects in the shallow water. Both of these kinds occasionally 

 contribute fragments to the sea-sand. 



